2,199 research outputs found

    On the Stability of Thermonuclear Burning Fronts in Type Ia Supernovae

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    The propagation of cellularly stabilized thermonuclear flames is investigated by means of numerical simulations. In Type Ia supernova explosions the corresponding burning regime establishes at scales below the Gibson length. The cellular flame stabilization - which is a result of an interplay between the Landau-Darrieus instability and a nonlinear stabilization mechanism - is studied for the case of propagation into quiescent fuel as well as interaction with vortical fuel flows. Our simulations indicate that in thermonuclear supernova explosions stable cellular flames develop around the Gibson scale and that deflagration-to-detonation transition is unlikely to be triggered from flame evolution effects here.Comment: 6 pages, 2 figures, to appear in the proceedings of the IAU Colloquium 192, "Supernovae (10 years of SN1993J)", 22-26 April 2003, Valencia, Spain, Eds. J.M. Marcaide and K.W. Weiler, Springer Verla

    Leibnizian, Robinsonian, and Boolean Valued Monads

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    This is an overview of the present-day versions of monadology with some applications to vector lattices and linear inequalities.Comment: This is a talk prepared for the 20th St. Petersburg Summer Meeting in Mathematical Analysis, June 24-29, 201

    Full counting statistics of a chaotic cavity with asymmetric leads

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    We study the statistics of charge transport in a chaotic cavity attached to external reservoirs by two openings of different size which transmit non-equal number of quantum channels. An exact formula for the cumulant generating function has been derived by means of the Keldysh-Green function technique within the circuit theory of mesoscopic transport. The derived formula determines the full counting statistics of charge transport, i.e., the probability distribution and all-order cumulants of current noise. It is found that, for asymmetric cavities, in contrast to other mesoscopic systems, the third-order cumulant changes the sign at high biases. This effect is attributed to the skewness of the distribution of transmission eigenvalues with respect to forward/backward scattering. For a symmetric cavity we find that the third cumulant approaches a voltage-independent constant proportional to the temperature and the number of quantum channels in the leads.Comment: new section on probability distribution and new references adde

    Weighted ergodic theorems for Banach-Kantorovich lattice Lp(^,μ^)L_{p}(\hat{\nabla},\hat{\mu})

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    In the present paper we prove weighted ergodic theorems and multiparameter weighted ergodic theorems for positive contractions acting on Lp(^,μ^)L_p(\hat{\nabla},\hat{\mu}). Our main tool is the use of methods of measurable bundles of Banach-Kantorovich lattices.Comment: 11 page

    The Effect of Air on Granular Size Separation in a Vibrated Granular Bed

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    Using high-speed video and magnetic resonance imaging (MRI) we study the motion of a large sphere in a vertically vibrated bed of smaller grains. As previously reported we find a non-monotonic density dependence of the rise and sink time of the large sphere. We find that this density dependence is solely due to air drag. We investigate in detail how the motion of the intruder sphere is influenced by size of the background particles, initial vertical position in the bed, ambient pressure and convection. We explain our results in the framework of a simple model and find quantitative agreement in key aspects with numerical simulations to the model equations.Comment: 14 pages, 16 figures, submitted to PRE, corrected typos, slight change

    Radar plots: A novel modality for displaying disparate data on the efficacy of eluxadoline for the treatment of irritable bowel syndrome with diarrhea

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    BackgroundPatients with irritable bowel syndrome with diarrhea (IBS‐D) experience a range of abdominal and bowel symptoms; successful management requires alleviation of this constellation of symptoms. Eluxadoline, a locally active mixed μ‐ and κ‐opioid receptor agonist and δ‐opioid receptor antagonist, is approved for the treatment of IBS‐D in adults based on the results of 2 Phase 3 studies. Radar plots can facilitate comprehensive, visual evaluation of diverse but interrelated efficacy endpoints.MethodsTwo double‐blind, placebo‐controlled, Phase 3 trials (IBS‐3001 and IBS‐3002) randomized patients meeting Rome III criteria for IBS‐D to twice‐daily eluxadoline 75 or 100 mg or placebo. Radar plots were prepared showing pooled Weeks 1‐26 response rates for the primary efficacy composite endpoint (simultaneous improvement in abdominal pain and stool consistency), stool consistency, abdominal pain, urgency‐free days, and adequate relief, and change from baseline to Week 26 in IBS‐D global symptom score, abdominal discomfort, abdominal pain, abdominal bloating, and daily number of bowel movements.Key ResultsThe studies enrolled 2428 patients. Eluxadoline increased Weeks 1‐26 responder proportions vs placebo for the composite endpoint, stool consistency, abdominal pain, urgency‐free days, and adequate relief. Changes from baseline to Week 26 in IBS‐D global symptom score, abdominal discomfort, abdominal pain, abdominal bloating, and number of bowel movements were greater with eluxadoline vs placebo.Conclusions and InferencesData presentation in radar plot format facilitates interpretation across multiple domains, demonstrating that eluxadoline treatment led to improvements vs placebo across 13 endpoints representing the range of symptoms experienced by patients with IBS‐D.Data presentation in radar plot format can facilitate evaluation of the diverse array of symptoms and outcomes that are relevant to a symptom‐based condition like irritable bowel syndrome with diarrhea (IBS‐D). In 2 Phase 3 trials, eluxadoline treatment improved stool consistency and frequency, abdominal pain, bloating and discomfort, feelings of urgency, global symptom score, and adequate relief. Radar plots provide a visual demonstration of improvements with eluxadoline across 13 endpoints encompassing the diverse constellation of symptoms experienced by patients with IBS‐D.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145265/1/nmo13331_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145265/2/nmo13331.pd
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